The present invention relates to a binocular tube for microscopes having at least two image inlets and/or outlets for attachments, and a switchable mirror turret by which the objective ray path can be switched as desired to the eyepiece either directly or via an attachment (bypass loop) connected to the image inlet or outlet.
Such tubes are known, for instance, from West German Pat. No. 24 06 415, the application for which was published on Oct. 24, 1974, in which the attachment is a photometer attachment. With the mirror (prism) inserted, the entire light coming from the objective is reflected into the eyepiece, while with the mirror not inserted, the object is focused via an image outlet onto the reflecting photometer diaphragm and reflected back by the latter through a second image inlet into the eyepiece. In this switched position, the image of the diaphragm is then superimposed on the microscopic image.
This known tube is not directly adapted to bear other attachments instead of the photometer device described.
From U.S. Pat. No. 3,421,806 of Weber, granted Jan. 14, 1969, there is known a photometer microscope which has a first beam path used both as outlet and inlet for the reflecting back of an illuminated diaphragm and another, second beam path used as outlet for an attachment camera as shown in FIG. 5 of the patent.
The arrangement described therein of the mirror elements has the disadvantage that light which is conducted to the photometer or is reflected via the diaphragm reflection into the eyepiece is passed several times, namely up to five times, through beam splitters, whereby a considerable reduction in light intensity results.
The object of the present invention is to create a binocular tube which is suitable for the attaching of different attachments and on which therefore a still or motion picture camera unit or a plotting apparatus can be placed instead of a photometer attachment.